Change of structure and some physical properties of level fast ice during the spring and summer period of 2014 in the vicinity the research station “Ice base Cape Baranov”

Abstract

The determination of the main physical properties of the fast ice around the research station “Ice base Cape of Baranov” was carried out from May 23 to August 7, 2014. At the beginning of the observations the ice was a system of three main layers reflecting the conditions of fast ice formation. The top 70 cm of the ice was formed under the conditions of dynamic variability. The ice formation to the level of 110 cm was more stable, and the lowerst layer below 110 cm grew without hummocking and thawing. In the second decade of June the ice accretion began on top due to recrystallization on snow and ice boundary. In the third decade of June the accretion process at the ice-snow interface was replaced by surface melting and destruction layer development. These changes are assumed to begin as maximum air temperatures keep above zero. By the second decade of July all the ice core had undergone serious internal changes. In the third decade of July the process of inter-crystalline-binding degradation affected the whole ice core.From the end of the third decade of June the formation of plate-like crystals was registered at the lower ice border, as well as the accretion of new ice in the form of layesr of various thickness and density. The process had reached the maximum by mid July when new ice up to 30 cm thick was formed. In the third decade of July this ice begun to melt. New ice accretion is primarily due to the presence of a layer of desalinated water under the ice.